The present invention relates generally to earphones which cover the ear, and more particularly to earphones for infants for use in hearing screening tests.
It is known to conduct tests to identify hearing impairments in humans (also known as xe2x80x9chearing screeningxe2x80x9d). It is critical and advantageous to determine whether or not any hearing impairments exist at an early age, such as in newborns and infants. This is because the earlier a problem is diagnosed and therapy undertaken, the more likely the therapy or other intervention will minimize the potential problems and costs associated with the identified hearing impairments or loss.
Over the years, hearing screening techniques have been developed which inject a sound input into the ear and detect a response to that input. The response is related to the characteristics of the sound input, the conditions inside the ear, the vibration transmission mechanism of the ear and the neural pathway through to the brain. The response can be analyzed to assess the hearing of the patient.
In many cases, and in particular in the case of infants, hearing screening is performed by using an earphone having a cavity that fits closely about the ear. Auditory tones or xe2x80x9cclicksxe2x80x9d are fed into the earphone cavity, and the response generated by the patient""s ear and the neural activity system in response to the auditory tones is sensed by a transducer. The transducer may be, for example, a microphone, suitable electrodes, an electroencephalogram (used in auditory brainstem response tests), piezo electric materials and like devices that read signals representative of the response to the auditory input. These signals are then processed and the result (as well as the detected signals, if desired) can be displayed on a monitor or other viewing device for analysis of the patient""s hearing.
A common problem using this method is that ambient noises are capable of interfering with the stimulus or the response signals, and, thus, the result. In most cases, the monitoring equipment has mechanisms, such as microphones, for detecting and compensating for ambient background noise. However, compensating for noise inside the cavity is difficult. This difficulty is compounded when the earphones do not adhere fully to the skin surface of the patient""s head. Any xe2x80x9cpulling awayxe2x80x9d from the head can create a gap which, in turn, may result in xe2x80x9cleakagexe2x80x9d of acoustic energy. Such leakage may effect any testing. Further, the earphone must be precisely placed on the head of the patient such that the cavity is centered over the ear or the measured response may not be accurate.
Another concern when testing the hearing of children is the delivery of the acoustic energy. Damage to the ear can result if too much acoustic energy is delivered. Typically, the transducers commonly employed to deliver this acoustic energy are designed to work in combination with the earphone assembly and deliver a controlled amount of acoustic energy. However, when earphones are used in combination with other transducers, the resultant acoustic energy is less certain and thus may be too high, causing damage to the ear.
U.S. Pat. No. 4,930,520 to Liverani, incorporated herein by reference, provides a disposable earphone for testing the hearing in infants which includes a toroidal baffle of anechoic, insulative foam, a rigid clear planar window plastic sheet adhered to one side of the baffle defining a cavity, and an adhesive coating on the other side of the baffle for temporarily bonding the disposable earphone to the region surrounding the infant""s ear. The earphone is capable of being used with transducers for transferring acoustical energy to the infant""s ear for testing. The Liverani device has been commercialized and is sold under the trademark EAR COUPLERS(copyright) disposable earphones by Natus Medical Incorporated, the assignee of this invention.
U.S. Pat. No. 5,826,582 to Sheehan et. al., incorporated herein by reference, relates to an earphone assembly for use with a hearing screener particularly suitable to test infants for hearing impairment. The earphone includes a generally D-shaped reusable cover formed of a rigid material. The cover has a back wall, a side wall extending from the perimeter of the back wall to define a cavity, a port in the cover to receive a transducer, and a generally D-shaped disposable element that is adhesively coated on two sides to be secured to the cover and to the patient""s head. The cover may have a notch located along the perimeter of the re-usable body for removing the disposable element. A liner is used to cover the disposable element adhesive sides to protect them from contamination during packaging and prior to use. The disposable element may have a die cut so that a portion of it can be removed to make the earphones adjustable for infants with large ears.
One difficulty with existing earphone assemblies is that the baffles or covers must deform to match the contour of the patient""s head. In particular, near the jaw, the patient""s head is naturally contoured and does not present a flat mating surface for the earphones. When using a compressible, elastic material for the baffle, internal shear stresses are created between adjacent portions of the baffle since these portions will be compressed or stretched different amounts. As the material seeks to return to its original shape, certain portions of the baffle may be pulled off the patient""s head, creating a xe2x80x9cleakxe2x80x9d for acoustic energy. This problem is exacerbated by the rigid plates employed as lids that transfer the pull to the baffle material. While earphones can be formed to match the contour of a particular patient""s head, this may be inordinately expensive and may require custom earphones for each patient and earphones designed specifically for either the left or right ear.
Thus, although the aforementioned prior art devices are useful in hearing screening there remains a need for an improved earphone that overcomes the inadequacies of the known devices and, further, provides advances that improves the attenuation of ambient and external noise inside the cavity of the earphone. In particular, an inexpensive device for readily and accurately matching the head contour without resulting in a substantial loss in acoustic energy during testing is required.
Accordingly, it is an advantage of an aspect of the instant invention to provide an earphone assembly capable of flexing to better match the contours of the patient""s head.
It is an advantage of another aspect of the invention to provide an earphone assembly that is capable of being used with ears of different sizes and for either the left or the right ear.
It is an advantage of another aspect of the invention to provide an earphone assembly that is generally insulated from external noise.
It is yet an advantage of another aspect of the invention to provide an earphone assembly that includes a visual grid or target to assist caregivers in positioning the earphone about the ear during hearing screening tests.
It is an advantage of yet another aspect of the invention to provide an earphone assembly that includes a flexible lid cooperating with a flexible baffle to fit snugly on the heads of patients of various sizes.
It is an advantage of yet another aspect of the invention to provide an earphone assembly with an increased adhesive area for better securement to a patient""s head.
It is an advantage of yet another aspect of the instant invention to provide an earphone assembly that is flexible and yet inexpensive to manufacture.
It is an advantage of yet another aspect of the instant invention to provide an earphone assembly that delivers consistent acoustic energy during a hearing test.
In accord with one aspect of the invention, an earphone is provided that includes an annular baffle having an outer surface and an inner surface separated by a height as well as an interior wall and an exterior wall separated by a thickness. The interior wall defines a central chamber. A transparent, flexible lid is attached to the baffle along the outer surface, completely covering the central chamber and forming an acoustic seal with the baffle. The lid has an inner face and an outer face. The flexibility of the earphone is improved by creating hinges in the lid and by providing cuts, or other discontinuities, in the baffle. For example, a radial cut may be disposed in the annular baffle. Further, a circumferential cut may also (or alternatively) be disposed in the baffle, extending from the inner surface and disposed between the exterior wall and the interior wall. At least one hinge may be disposed on the flexible lid. To improve the attachment of the earphone to the patient""s head, tabs are mounted to the exterior wall. An adhesive material is applied to the inner surface of the annular baffle and to the tabs, thereby increasing the adhesive surface compared to existing earphones.
In accord with another aspect of the invention, an earphone assembly is provided for use with a transducer for hearing screening. An annular baffle includes an outer surface and an inner surface separated by a height. The baffle defines a central chamber. A flexible lid is attached to the baffle along the outer surface and covering the central chamber. An aperture extends through the baffle to the central chamber for conveying acoustic energy to and from the chamber. The flexible lid permits the baffle to more readily conform to the patient""s head.
Certain implementations of this aspect of the invention may provide any combination of the following features: the flexible lid includes an inner face and an outer face, a hinge is disposed along a face of the flexible lid and an acoustic seal is formed between the inner face of the lid and the outer surface of the baffle; the hinge is a groove disposed in the outer face of the flexible lid; the lid includes an inner face and outer face and a plurality of hinges are disposed in the outer face of the lid; at least two grooves intersect; at least two grooves intersect at an angle of about 70xc2x0; the flexible lid is transparent and a target is positioned on the lid; the annular baffle includes a first upper quadrant, a second upper quadrant, a first lower quadrant and a second lower quadrant, and the hinge extends generally from the first upper quadrant to the second lower quadrant; at least two grooves extend parallel to each other; at least one cut is disposed in the annular baffle extending from the inner surface at least partly through the height of annular baffle; the annular baffle comprises four contiguous quadrants and cuts are positioned between at least three quadrants, extending radially outward from the central chamber; the annular baffle has an exterior wall and an interior wall separated by a thickness, and a circumferential cut extends at least partly through the thickness of the annular baffle from the inner surface disposed between the exterior wall and the interior wall; radial slits extend at least partly through the annular baffle; the annular baffle further comprises an interior wall defining the central chamber, and an exterior wall, and that the assembly further comprises tabs mounted to the exterior wall and an adhesive applied to the inner surface of the annular baffle and the tabs; the baffle has an interior wall with an oval shape defining the central chamber, an exterior wall having a rectangular shape and an adhesive applied to the inner surface of the annular baffle.
In accord with another aspect of the invention, an earphone assembly is provided for use during hearing screening. A baffle forms a closed loop and defines a central chamber. The baffle has an inner surface, an outer surface, an interior wall and an exterior wall. A lid is attached to the outer surface of the baffle. Means are provided for conveying sound to the central chamber disposed in the wall. At least one cut is disposed in the baffle to improve the ability of the baffle to conform to the patient""s head.
Certain implementations of this aspect of the invention may provide any of combination of the following features: the cut comprises at least one slit disposed along the exterior wall of the baffle, extending circumferentially about the baffle; the cut is disposed along the interior wall of the baffle, extending circumferentially about the central chamber; the cut extends radially from the interior wall to the exterior wall; tabs are mounted to the exterior wall; means are provided for increasing the flexibility of the lid; the flexibility increasing means comprises at least one hinge disposed on the lid; the hinge is a groove extending from the first upper portion of the wall to the second lower portion of the wall; the flexibility increasing means comprises a plurality of grooves disposed on the lid, the lid is made of a substantially transparent material and the grooves form a visible grid; a slot is disposed along an interior wall of the baffle extending circumferentially about the central chamber and the lid is seated on the slot; a visible translucent target is positioned on the lid; the cut comprises a circumferential cut extending at least partly through the thickness of the annular baffle from the inner surface and disposed between the exterior wall and the interior wall; the cut comprises radial slits extending at least partly through the annular baffle; a first set of radial slits extend from the inner wall to the circumferential cut and a second set of radial slits extend from the circumferential cut to the outer wall; the first set of radial slits are offset from the second set of radial slits; the lid has an edge which is disposed on the outer surface between the interior wall and the exterior wall; a corner formed by the outer surface and the exterior wall is beveled; a corner formed by the inner surface and the exterior wall is beveled; a corner formed by the inner surface and the interior wall is beveled.
In accord with yet another aspect of the invention, an earphone assembly is provided having a baffle that forms a closed loop. The baffle has an inner surface, an outer surface, an interior wall, an exterior wall, a thickness extending from the interior wall to the exterior wall and a height extending from the inner surface to the outer surface. The interior wall defines a central chamber having an oval shape. A flexible lid is attached to the outer surface of the baffle, covering the central chamber and forming an acoustic seal with the outer surface of the baffle. Means are provided for conveying sound to the central chamber disposed in the baffle. A cut is disposed in the baffle. The cut in the baffle and the flexible lid cooperate to allow the earphone assembly to conform to the patient""s head.
Certain implementations of this aspect of the invention may provide any combination of the following features: the lid is cup-shaped with a concave surface surrounded by a lip which itself is attached to the outer surface of the baffle by an adhesive such that the concave surface faces the baffle; a slot is disposed in the outer surface of the baffle and the lip is seated in the slot; a step is formed in the outer surface of the baffle and the lip is seated snugly about the step; and the lip is contoured to approximate the contour of the patient""s head.
In accord with another aspect of the invention, an earphone is provided for attachment to skin of a patient undergoing hearing screening. An annular baffle includes an outer surface and an inner surface separated by a height as well as an interior wall and an exterior wall separated by a thickness. The interior wall defines a central chamber. Means are provided for covering the chamber and forming an acoustic seal with the outer surface of the annular baffle. Means are provided for increasing the flexibility of the baffle. Means are provided for conveying acoustic energy to the chamber. Means are provided for increasing the flexibility of the covering means. Means are provided for forming an acoustic seal between the inner surface of the annular baffle and the skin of the patient.
Certain implementations of this aspect of the invention may provide any combination of the following features that: the baffle flexibility increasing means comprises at least one radial cut in the annular baffle extending at least partly through the annular baffle; the covering means comprises a lid and the means for increasing the flexibility of the covering means comprises at least one groove disposed on the lid.
In accord with another aspect of the invention, an earphone assembly is provided. A baffle forms a closed loop and has an inner surface, an outer surface, an interior wall, and an exterior wall. A thickness extends from the interior wall to the exterior wall. A height extends from the inner surface to the outer surface. The interior wall defines a central chamber. A cup-shaped lid with a concave surface is surrounded by a lip. The lip is attached to the outer surface of the baffle such that the concave surface faces the baffle. Means disposed in the baffle are provided for conveying sound to the central chamber.
Certain implementations of this aspect of the invention may provide any combination of the following features: a slot is disposed in the outer surface of the baffle and the lip is seated in the slot; a step is formed in the outer surface of the baffle wherein the lip is seated snugly about the step.
In accord with another aspect of the invention, an earphone assembly for use with a transducer for hearing screening is provided. An annular baffle includes an outer surface and an inner surface separated by a height, and an interior wall and an exterior wall separated by a thickness. The interior wall defines a central chamber. A lid is attached to the baffle along the outer surface and covering the central chamber. An aperture extends through the baffle to the central chamber for conveying acoustic energy to the chamber. Tabs are attached to the exterior wall of the annular baffle.
In accord with another aspect of the invention, an earphone assembly is provided for use with a transducer for hearing screening. The assembly includes an annular baffle having an outer surface and an inner surface separated by a height, and an interior wall and an exterior wall separated by a thickness. The interior wall defines a central chamber. A transparent lid is attached to the baffle along the outer surface, completely covering the central chamber and forming an acoustic seal with the baffle. The lid has an inner face and an outer face. At least one cut extends at least partly through the annular baffle. An adhesive material applied to the inner surface of the annular baffle.
Certain implementations of this aspect of the invention provide that: a circumferential cut is disposed in the outer surface of the annular baffle; a proprietary connection is disposed between the annular baffle and the transducer; a means is provided for sending a signal identifying the baffle mounted in the baffle and a means are provided for reading the identifying signal operably engaged to the transducer to determine the identity of the baffle; a means is provided for controlling the transducer based, at least in part, upon the identifying signal; the identifying means comprises a computer chip mounted in the baffle; the proprietary connection comprises an aperture in the baffle having a non-circular cross-section designed to match the non-circular cross-section of the transducer.
In accord with another aspect of the invention, a method is provided for assembling an earphone for use with a transducer for hearing screening. An annular baffle is provided including an outer surface and an inner surface separated by a height. A central chamber is defined within the baffle. A flexible lid is attached to the baffle along at least a portion of the outer surface. The central chamber is covered with the flexible lid. A port is provided through the baffle to the central chamber for conveying acoustic energy to and from the chamber. Certain implementations of this aspect of the invention provide that cuts are inserted into the baffle and the hinges are provided on the lid.